心率变异性复杂度分析和脑电双频谱指数在监测全身麻醉时的相关性

目的：观察全身麻醉时心率变异性分析中复杂度和脑电双频谱指数（BIS）的变化,探讨复杂度和BIS在监测麻醉深度时的相关性。方法：30例全身麻醉病人,测定麻醉前（T1）、诱导插管（T2）、术中（T3）、苏醒（T4）4个时间点各5min的心率（HR）、平均动脉压（MAP）、脑电双频谱指数（BIS）和复杂度变化。结果：HR在T2、T3和T4较T1值升高（P〈0.01或0.05）。MAP在T2时较T1值降低（P〈0.05）,T3和T4较T1值升高（P〈0.05）,而T3和T4相比变化较大（P〈0.01）。BIS值在各时点较T1值下降明显（P〈0.01）,其中T4较T1略下降（P〈0.05）,T3与T2时相比明显降低（P〈0.01）,而T4较T3明显升高（P〈0.01）。复杂度值的T1值均大于各个点（P〈0.01或0.05）,其T4较T2和T3时升高（P〈0.05）,T3较T2时升高（P〈0.05）。结论：作为心率变异性非线性指标的复杂度能描述围术期心脏自主神经功能状态的变化,但其与BIS并无相关性。     

脑电熵在麻醉深度监测中的意义

随着肌松药和镇痛药等药物的联合应用,现代全身麻醉的深度、患者的意识状态常常被掩盖或难以判断.以往的传统体征(血压、心率、呼吸和瞳孔等)已不能准确地反映麻醉深度.目前,有关研究重点集中在脑电活动方面,如脑电双频指数(bispectral index,BIS)、脑电熵(entropy)、听觉诱发电位等.现就entropy在麻醉深度监测中的意义及其研究进展作一综述,并与脑电双频指数进行比较.     

脑电熵在临床麻醉深度监测的应用

麻醉深度一直是麻醉领域中备受关注的问题。全身麻醉是一种复杂且特殊的状态．包括催眠、记忆缺失、疼痛应激抑制和肌肉松弛等多方面的因素构成。传统的生命体征．如：心率、血压．呼吸．瞳孔等．已不能准确的反应麻醉深度。随着脑电技术的发达．目前已有听觉诱发电位、脑电双频指数（bispectral index．BtS）．脑电熵（Entropy）等多种监测方法．本文就脑电熵在麻醉深度中的应用以及这几年的进展作一综述。     

脑电非线性分析参数近似熵对麻醉深度的监测

脑电（EEG）数字化分析已广泛用于麻醉中大脑皮层的功能监测，应用单一的数字化EEG参数分析麻醉药的中枢效应更为直观、方便。已知EEG信号起源于高度非线性系统，近年来EEG的非线性分析对围术期脑功能监测发展很快。以下就脑电非线性参数之一近似熵，对麻醉深度的监测基础和临床研究作一综述。     

麻醉状态下氟马西尼对患者脑电双频指数的影响

目的 评估七氟醚麻醉下氟马西尼对患者麻醉深度及脑电双频指数(BIS)的影响.方法 20例ASA Ⅰ或Ⅱ级患者择期全麻下行妇科腹腔镜手术.当麻醉初期BIS(47±3)时静注氟马西尼0.01 mg/kg,记录给药(氟马西尼)前及给药后2、4、6、8、10、15、20 min 7个时点的SBP、DBP、MAP、HR、SpO_2及BIS值.结果 各时点的SBP、DBP、MAP、HR、SpO_2及BIS值差异均无统计学意义.结论 氟马西尼对七氟醚麻醉下患者的镇静程度无明显拮抗作用.     

脑电非线性分析参数近似熵对麻醉深度的监测

脑电(EEG)数字化分析已广泛用于麻醉中大脑皮层的功能监测,应用单一的数字化EEG参数分析麻醉药的中枢效应更为直观、方便。已知EEG信号起源于高度非线性系统,近年来EEG的非线性分析对围术期脑功能监测发展很快。以下就脑电非线性参数之一近似熵,对麻醉深度的监测基础和临床研究作一综述。     

芬太尼血浆浓度对麻醉清醒时异丙酚浓度及脑电双频指数的影响

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吸入麻醉下内隐记忆与脑电双频谱指数的关系

目的 研究相同ＭＡＣ水平的吸入麻醉药对内隐记忆的影响,分析内隐记忆消失的界值。方法 ５４例行择期腹部手术患者,随机分为异氟醚、七氟醚、地氟醚３组（每组１８例）,麻醉采用吸入麻醉复合硬膜外麻醉,每组又依吸入麻醉浓度不同分成３个亚组（每组６例）,吸入麻醉药呼末ＭＡＣ值分别为０．４、０．５、０．６,监测患者入室后、麻醉后、切皮后、术中的双频谱指数（ＢＩＳ）,９５％的谱边缘频率（ＳＥＦ）,调查患者术后８ｈ     

心率变异性近似熵分析法与脑电双频谱指数间的相关性

目的:观察全身麻醉时心率变异性分析中近似熵分析法与脑电双频谱指数(BIS)在监测麻醉深度时的相关性。方法:对40例全身麻醉病人测定麻醉前(T1)、诱导插管(T2)、术中(T3)、苏醒(T4)4个时间点各5min的心率(HR)、平均动脉压(MAP)、脑电双频谱指数(BIS)和近似熵(ApEn)变化。结果:HR在T2、T3和T4均较T1值升高(P0.01～0.05)。MAP在T2时较T1值降低(P0.05),T3、T4较T1值升高(P0.05),而T4比T3明显升高(P0.01)。BIS值在麻醉后各时点均较T1值下降明显(P0.01),其中T4也较T1下降(P0.05),T3与T2时相比明显降低(P0.01),而T4较T3明显升高(P0.01)。近似熵值的T1值均大于其他各时点(P0.01～0.05),其T4较T3时点升高(P0.01),T3较T2时点降低(P0.05)。结论:作为心率变异性的非线性分析方法指标的近似熵分析法,能描述围术期心脏自主神经功能状态的变化,但其与BIS并无相关性。     

相同脑电双频谱指数不同麻醉药切皮时脑电图与心率变异的比较

脑电双频谱指数（ＢＩＳ）被认为是当今评价麻醉深度的较为准确可靠的方法之一,近来研究也发现,心率变异（ＨＲＶ）可以定量反应全麻药物对自主神经功能的影响,因此许多研究认为其可以用于麻醉深度的判断。本研究利用脑电双频谱指数作为麻醉深度的参考标准,在相同的ＢＩＳ值（５０）下,观察单纯异氟醚麻醉和异氟醚及Ｎ２Ｏ复合麻醉两种麻醉方法手术切皮时病人的ＢＩＳ和ＨＲＶ改变,探讨两者在麻醉深度监测中的不同意义。 资料与方法 选择 ＡＳＡⅠ— Ⅱ级在全麻下行择期子宫全切手术病人２０例,年龄３４～５３岁,体重５２～７５ｋｇ…     

Correlation between EEG and heart rate variation in deep enflurane anaesthesia

Variations in heart rate during deep enflurane anaesthesia were studied in 11 women admitted for elective surgery. Correlation was found between heart rate variations and bursts and suppressions in the EEG patterns. The onset of bursts coincided with accelerating heart rate, and the onset of suppressions was combined with a fall in heart rate in all patients. The correlation is not explained by ventilation arrhythmia. Both the cortical electrical activity and heart rate fluctuation are probably controlled by the same subcortical factor.     

连续腰麻与连续硬膜外麻醉用于高危老年患者下肢手术的比较

目的探讨连续腰麻用于应用于高危老年患者下肢手术的可行性。方法40例拟行下肢手术的老年患者,年龄68～101岁,ASAⅢ～Ⅳ级,按手术种类配对,患者随机分为硬膜外麻醉组(EA组)、连续腰麻醉组(CSA组),每组20例。EA组按常规行硬膜外麻醉,CSA组按常规行连续腰麻。于麻醉前(T0,基础值)、麻醉平面满意时(T1)、切皮后1h(T2)、术毕时(T3)抽取动脉血测乳酸浓度,常规监测动脉压(ABP)、心率(HR)、脉搏氧饱和度(SPO2),记录两组患者辅用麻黄素、氟芬合剂的情况。结果CSA组麻醉前、后各时点的MBP、HR、SpO2均无显著性变化;EA组硬膜外用药后,MBP、HR明显下降(P<0.05)。从T0至T2时段,EA组有98%的患者需辅用麻黄素,显著高于CSA组(15%)(P<0.01),EA组麻黄素用量[(30.5±3.1)mg]显著高于CSA组[(4.1±0.5)mg](P<0.01)。EA组有40%的患者术中需辅用氟芬合剂,显著高于CSA组(15%)(P<0.05)。在T1、T2、T3各时点EA组动脉血乳酸浓度均高于CSA组(P<0.05)。CSA组术后未见连续腰麻相关并发症。结论与硬膜外麻醉相比,连续腰麻麻醉效果确切,对循环干扰小,非常实用于高危老年患者的下肢手术。     

异丙酚复合芬太尼或瑞芬太尼靶控静脉麻醉与静吸复合麻醉的比较

目的 评价异丙酚和瑞芬太尼靶控静脉麻醉的诱导和术后苏醒过程。方法 ASA Ⅰ-Ⅱ级择期行腹腔镜胆囊切除手术的病人60例,年龄<65岁,随机分为静吸复合麻醉(C)组、异丙酚瑞芬太尼靶控(R)组及异丙酚芬太尼靶控(F)组,每组20例。观察麻醉诱导及气管插管时的血压、心率;记录术毕停药后病人自主呼吸恢复时间、呼之睁眼时间、拔管时间、定向力恢复时间和离开恢复室时间;观察病人拔管后即刻、离开恢复室、拔管后1、3和24h的意识状态(OAAS),认知功能测试(MMSE),疼痛评分(VRS)及主诉需要阿片药镇痛的时间;观察恶心呕吐等副反应,记录术中知晓的发生率和病人满意度等。结果 ①C组诱导时的舒张压低于R组和F组,低血压者多于R组,插管反应发生率高于R组。F组的插管反应发生率高于R组。②三组病人术后自主呼吸恢复时间、呼之睁眼时间、拔管时间差异无显著性,但F组的定向力恢复时间和离开术后恢复室(PACU)的时间早于C组。F组病人在拔管后即刻、离开PACU时、拔管后1h和3h的OAAS评分高于C组,R组病人离开PACU时的OAAS评分高于C组。F组病人拔管后1h的MMSE评分高于C组。R组病人在拔管后即刻、离开PACU时、拔管后1h和术后24h的VBS评分高于C组和F组,需要阿片药镇痛者R组多于其他两组。三组病人术后的恶心呕吐发生率差异无显著性。结     

The effect of nitrous oxide on EEG spectral power during halothane and isoflurane anaesthesia

The effect of N2O on EEG during halothane and isoflurane anaesthesia was studied in 24 elective-surgery patients. The total EEG power and various power bands were analysed with fast Fourier transform power spectra. Anaesthesia was induced by mask. EEG analysis was performed from the data collected before induction and during steady-state halothane and isoflurane anaesthesia with and without N2O. In both halothane and isoflurane anaesthesia, N2O had a significant effect on EEG. Alpha- and beta-range EEG power and total power decreased during N2O in both groups. Delta- and theta-range power increased during N2O in the halothane group. The study shows that the effect of nitrous oxide should be taken into consideration when EEG is being studied or monitored during anaesthesia.     

复合异丙酚全麻中麻醉深度指标的相关性

目的 探讨复合异丙酚全麻中麻醉深度指标的相关性。方法 选择ASA Ⅰ～Ⅱ择期手术患者18例,行血压、心率、脑电、心率变异性监测,并测定异丙酚血药浓度。调整异丙酚的泵注速度,使收缩压(SBP)的波动幅度≤20％基础值,双频谱指数(BIS)维持在30～60之间。结果 异丙酚血药浓度与BIS、平均动脉压(MAP)有负相关关系(P<0.01),相关程度为BIS>MAP,心率(HR)与MAP呈正相关(P<0.01);心率变异性低频(LF)、高频(HF)与HR均有负相关关系(P<0.01),LF与HF有正相关关系(P<0.01),LF、HF与MAP、BIS、异丙酚血药浓度无相关关系(P>005)。结论 LF、HF可反映心脏交感、迷走张力的活动变化,而不能反映麻醉的意识状态。可通过BIS、平均动脉压来调整异丙酚血药浓度。     

Supreme与ProSeal两种喉罩在小儿麻醉中应用的对比研究

目的 评价一次性双腔喉罩Supreme(laryngeal mask airway Supreme,SLMA)与反复使用型双腔喉罩ProSeal (laryngeal mask airway ProSeal,PLMA)用于小儿麻醉的效果及安全性. 方法 择期在全身麻醉下行手术的患儿60例,年龄9个月～5岁,体重10 kg～20 kg,美国麻醉医师协会(ASA)分级Ⅰ～Ⅱ级,采用随机数字表法随机分为SLMA组(S组)和PLMA组(P组),每组30例.麻醉诱导:咪达唑仑0.1 mg/kg、阿托品0.01 mg/kg、丙泊酚2 mg/kg、芬太尼2μg/kg、罗库溴铵0.6 mg/kg.记录置入喉罩的时间及难易度、首次置入成功率、口咽漏出压(oropharyngeal leak pressure,OLP)、胃管置入难易度,纤维支气管镜检查评定喉罩位置;记录置入喉罩前后患儿的心率、平均动脉压;记录术中患儿的吸入潮气量、呼出潮气量、气道峰压、肺顺应性以及拔除喉罩后不良事件与术后相关并发症的发生情况. 结果 S组OLP低于P组,分别为(19.7±2.2) cmH2O(1 cmH2O=0.098 kPa)和(22.3±3.4) cmH2O(P＜0.05).两组患儿在喉罩置入时间、首次置入成功率、纤维支气管镜下对位分级、胃管置入难易度、术中血流动力学及呼吸参数变化、术后不良事件发生情况上差异无统计学意义. 结论 PLMA的气道密闭性较SLMA更好,两种喉罩均可安全有效地用于小儿麻醉.     

不同麻醉深度指标在全麻镇静和镇痛监测中的比较

目的评价脑电双频指数(BIS)和电刺激-循环反应在全麻镇静和镇痛监测中的价值。方法20例择期手术全麻病人,将丙泊酚血浆靶浓度依次设定为1、2、3、4和5μg/ml,记录每一靶浓度下的BIS、SBP、DBP和HR值。维持意识消失时的效应室靶浓度,给予一次60mA强直电刺激,随后将雷米芬太尼效应室靶浓度依次设定为1、2、3、4和5ng/ml,达到每一靶浓度后给予一次同样电刺激,计算每次电刺激前后各指标的变化值(△BIS、△SBP、△DBP和△HR)。结果丙泊酚靶浓度依次增加,BIS值依次减少(P<0.05),两者之间呈负相关(r=-0.789,P<0.01)。不同雷米芬太尼靶浓度时,电刺激均未引起BIS的变化,但引起SBP、DBP和HR增加(P<0.05或P<0.01)。随着雷米芬太尼靶浓度增加,△SBP、△DBP和△HR呈下降趋势。雷米芬太尼靶浓度与△SBP和△HR之间呈负相关(r=-0.386和-0.302,P<0.05)。结论BIS对镇静药浓度变化敏感,对疼痛刺激反应差,电刺激-循环反应能够灵敏地反映镇痛水平,所以麻醉深度监测应该针对不同成分进行多指标、多方法的综合监测。     

缝隙连接在大鼠异丙酚和七氟醚麻醉中的作用

目的 评价缝隙连接在大鼠异丙酚和七氟醚麻醉中的作用.方法 雄性Wistar大鼠80只,体重210～260 g,采用随机数字表法,将大鼠随机分为8组(n=10):空白对照组(C组)、甘珀酸组(CA组)、异丙酚组(P组)、不同剂量甘珀酸+异丙酚组(CA1+P组、CA2+P组、CA3+P组)、七氟醚组(S组)、甘珀酸+七氟醚组(CA+S组).用立体定位仪定位大鼠侧脑室.C组侧脑室注射生理盐水2μl后腹腔注射生理盐水2ml,CA组侧脑室注射甘珀酸200μg后腹腔注射生理盐水2ml,P组、CA1+P组、CA2+P组和CA1+P组分别向侧脑室注射生理盐水2 μl、甘珀酸200、300和400μg后腹腔注射异丙酚5 mg/100 g,S组给予浓度梯度七氟醚,CA+S组侧脑室注射甘珀酸200μg后给予浓度梯度七氟醚,七氟醚初始浓度1%,梯度0.1%,记录翻正反射消失时间、翻正反射消失持续时间和翻正反射消失时七氟醚浓度.结果 C组与CA组大鼠均未出现翻正反射消失的麻醉作用;与P组比较,CA1+P组,CA2+P组,CA3+P组翻正反射消失时间缩短,翻正反射消失持续时间延长(P＜0.01);与CA+P组比较,CA2+P组,CA3+P组翻正反射消失时间缩短(P＜0.05);与S组比较,CA+S组翻正反射消失时七氟醚浓度减小(P＜0.05),翻正反射消失时间和消失持续时间差异无统计学意义(P＞0.05).结论 抑制缝隙连接功能虽然可强化异丙酚和七氟醚的麻醉作用,但不是其麻醉作用的主要机理.

Abstract：

Objective To evaluate the role of intercellular gap junction in the propofol and sevoflurane anesthesia in rats. Methods Eighty male Wistar rats weighing 210-260 g were randomly divided into 8 groups (n = 10 each): control group (group C), carbenoxolone group (group CA), propofol group (group P), different doses of carbenoxolone + propofol groups (groups CA1 + P, CA2 + P, CA3 + P), sevoflurane group (group S) and carbenoxolone + sevoflurane group (group CA + S). The animals ware anesthetized with intraperitoneal 10% chloraldurate 4 mg/kg and placed in a stereotactic apparatus to locate the lateral ventricle. In group C, after normal saline (NS) 2 μl was injected into the latersl ventricle, intraperitoneal NS 2 ml was injected. In group CA, after carbenoxolone 200 μg was injected into the lateral ventricle, intraperitoneal NS 2 ml was injected. In groups P,CA1 + P, CA2 + P and CA3 + P, NS 2 μl, and carbenoxolone 200, 300 and 400 μg were injected into the lateral ventricle respectively and then propofol 5 mg/100 g was injected intraperitoneally. Group S inhaled 1% sevoflurane (in increments of 0. 1% ) until the righting reflex was lost. Group CA + S inhaled 1% sevoflurane (in increments of 0.1% ) until the righting reflex was lost after carbenoxolono 200 μg was injected into the lateral ventricle. The time of loss of righting reflex, duration of loss of righting reflex and the sevoflurane concentration when the righting reflex disappeared were recorded. Results The loss of righting reflex did not appear in groups C and CA. Compared with group P, the time of loss of righting reflex was significantly shortened and duration of loss of righting reflex prolonged in groups CA1 + P, CA2 + P, CA3 + P ( P ＜ 0.01 ). The time of loss of righting reflex was significandy shorter in groups CA2 + P, CA3 + P than in group CA1 + P (P ＜ 0.05). The sevoflurane concentration when the righting reflex disappeared was significantly lower in group CA + S than in group S ( P ＜ 0.05 ). There was no significant difference in the time of loss of righting reflex and duration of loss of righting reflex between CA + S and S groups ( P ＞ 0.05). Conclusion Although inhibition of the function of gap junction can strengthen the anesthetic effects of propofol and sevoflurane, it is not the major mechanism.     

Comparison between general,spinal, epidural,and combined spinal-epidural anesthesia for cesarean delivery: a network meta-analysis

BackgroundThis study is a network meta-analysis to compare maternal and fetal outcomes associated with four different anesthetic techniques for cesarean delivery.MethodsAn arm-based, random-effects frequentist network meta-analysis was performed. A random effect model was selected considering deviance information criteria. Randomized trials reporting the following outcomes were included: Apgar score at 1- or 5-min; umbilical arterial and venous pH; umbilical arterial pH <7.2; and neonatal score at 2–4 hours. Loop-specific heterogeneity was evaluated by risk of odds ratio and τ². Quality of evidence was assessed using the GRADE approach.ResultsData from 46 randomized trials including 3689 women contributed to the study. There were significant differences in Apgar score ≤6 at 1 min between spinal versus general anesthesia (odds ratio 0.27, 95% confidence interval [CI] 0.13 to 0.55: moderate quality evidence) and Apgar scores at 1- and 5-min, favoring spinal anesthesia. Umbilical venous pH associated with epidural anesthesia was significantly higher than that with general anesthesia (mean difference 0.010, 95% CI 0.001 to 0.020: moderate quality evidence) or spinal anesthesia. Spinal anesthesia was ranked best for Apgar score ≤6 at 1-min (SUCRA=89.8), Apgar score at 1-min (SUCRA=80.4) and 5-min (SUCRA=90.5). Epidural anesthesia was ranked highest for umbilical venous pH (SUCRA=87.4) and neonatal score (SUCRA=79.3).ConclusionsSpinal and epidural anesthesia were ranked high regarding Apgar scores and epidural anesthesia was ranked high regarding umbilical venous pH, but the results were based on small heterogeneous studies with high or unclear risks of bias.